Quote Originally Posted by the image reaper
if venting directly from the lamp, do not use your fan on the exhaust-side, unless it is made for hot-air transfer ... like a furnace duct fan, for instance ... heat and electrical motors aren't a good idea, unless the fan is specifically designed for it ... :smokin:

You are soooo right! Take a Hydrofarm 465 or a 265 cfm fan,for instance.. Both these type fans are what they refer to as active air blowers. They are meant to be used inside the grow area and blown out of the room.A furnace duct fan keeps itself cool by being inside the cabinet. If you use an active air blower then it is advised that you not use it as an exhaust fan. You have 3 ways that air can be used to serve your needs.

Passive air
Exhaust air
Active air

Each one has it's own application.Passive air will occur when used with an exhaust or an active air blower/fan. Exhaust is where the fan is placed on the outside of the grow area.

Ga Grown!